The operational head of Interpol said on Thursday he is forbidden by the global police organisation’s own rules from investigating what happened to the Chinese government official who served as Interpol president for almost two years before vanishing in September on a trip to his homeland.

In his first public remarks about the disappearance of Meng Hongwei, secretary general Juergen Stock said he had “encouraged” Beijing to provide information about Meng’s location and legal status but could do no more.

Stock was speaking to journalists as Interpol members prepared to elect a new president to replace Meng at a general assembly in Dubai on November 18-21. Meng became the organisation’s president in November 2016.

Chinese authorities said they detained Meng, 64, on bribery charges, though his wife has described him as a victim of political persecution. He was one of China’s vice-ministers for public security and appears to be the latest high-ranking official to have been caught in a sweeping purge under Chinese President Xi Jinping.

Stock said his organisation learned of Meng’s disappearance on October 5 via media reports that came out after Meng’s wife said she had not heard from him since the end of September and reported him missing.

Interpol contacted Beijing, asking for clarification, according to Stock. A high-level Chinese delegation arrived at Interpol’s headquarters in Lyon on October 7, reported that Meng had written a resignation letter and advised that he was no longer a delegate from China to Interpol – meaning he could no longer serve as president.

China’s Interpol office transmitted the resignation letter to Interpol headquarters later that day. Pressed on whether Interpol had assurances Meng actually wrote it or did so without duress, Stock hedged.

“There was no reason for me to [suspect] that anything was forced or wrong,” he said.

Interpol appeared to accept the Chinese delegation’s explanation at face value and publicly announced that night that Meng had stepped down, without commenting on why or what happened.

Stock cited the structure and nature of the 192-member organisation, which provides a platform for member nations to share information on criminal activities, and the vast needs it fulfils in trying to contain ballooning transnational crime. Interpol databases are queried 200 times a second by police around the world, he said.

“We are a rules-based organisation. That is very important to understand,” Stock said, adding that the role of Interpol was “not to govern over member states”.

Stock said he was in “constant” contact with the national central bureau in Beijing that serves as Interpol’s point of contact in China. As secretary general, Stock manages Interpol’s day-to-day activities, while the agency’s elected president has a less hands-on, more symbolic role.

“We are strongly encouraging China” to come forth with details of Meng’s case, Stock said. He suggested Chinese officials would “when the right moment comes”.

Meng’s wife, Grace Meng, said last month that she received threats after her husband disappeared. She and their two children are under police protection in Lyon.

“There is no doubt this is a very regrettable situation,” Stock said. “But on the other hand, we have to ensure day-to-day operations … continue.”

He also conceded that Interpol must “mitigate negative impact” springing from Meng’s disappearance.

Interpol acts as a clearing house for national police services that want to hunt down suspects outside their borders. Governments have repeatedly tried to use Interpol to find political enemies, even though its charter explicitly proclaims its neutrality and prohibits use of police notices for political reasons.

Stock said that ensuring the notices are not misused has been one of his priorities.